According to an article published by CBS News, the French Parliament recently mandated that new buildings in commercial areas must have solar panels or plants covering part of their rooftops. The initial proposal required all new rooftops to be completely covered in plants or solar panels, but the government limited the regulation to just commercial infrastructure.

So why is France taking this step? Environmental activists are encouraging the use of solar panels to create electricity from renewable resources as opposed to more traditional and common methods. Last year alone, solar energy kept more than 100 million tons of carbon dioxide from being emitted. Creating gardens on rooftops has other environmental benefits too. According to the United States Environmental Protection Agency, green roofs bring shade and provide cool air to reduce temperatures. By absorbing heat, green rooftops act as insulators and can actually reduce the amount of energy needed to cool or warm a building. For example, a study conducted at Columbia University in 2012 found that during peak daytime summer hours, green roofs were on average 60 degrees Fahrenheit cooler than black rooftops.

Rooftop gardens gain popularity

Rooftop gardens may not seem particularly popular but they can be found in a variety of countries in addition to France, including the United States, Denmark and Greece. The EPA reported that in 2008, the United States had roughly 8.5 million square feet of green roofs installed or under construction.

In Copenhagen, Denmark, the city known for its happy residents, sustainability is on the forefront of architectsâ€™ minds, and green roofs and organic gardens within office buildings are fairly common. Many architecture firms such as Lendager Arkitekter are passionate about sustainability and it is the driving force for the companyâ€™s visions and designs. Sustainability was also on the mind of the architecture studio responsible for the garden atop the Tivoli Hotel & Congress Center, a famous landmark in the city. The rooftop garden includes vegetation, flower beds, perennials and trees.

According to the International Green Roof Association, Greece also has a Mediterranean-style green roof and itâ€™s located on top of the first LEED gold-certified building in the country, Karela Office Park. According to the U.S. Green Building Council, â€śthe aim was to create a structure that would process its own wastewater, capture light, create energy and provide habitat for wildlife while on the inside improve worker productivity and health.â€ť The entire buildingâ€™s design reflects daylight to lower energy usage and utilize natural light, and the roof has plants such as herbs and shrubs that make the entire workplace more environmentally friendly.